U.S. patent application number 14/856680 was filed with the patent office on 2016-01-07 for implanatable medical device for improved placement and adherence in the body.
This patent application is currently assigned to AngioDynamics, Inc.. The applicant listed for this patent is Navilyst Medical Inc.. Invention is credited to George Bourne, James Culhane.
Application Number | 20160001055 14/856680 |
Document ID | / |
Family ID | 32093227 |
Filed Date | 2016-01-07 |
United States Patent
Application |
20160001055 |
Kind Code |
A1 |
Bourne; George ; et
al. |
January 7, 2016 |
Implanatable Medical Device for Improved Placement and Adherence in
the Body
Abstract
A medical device comprises a flexible member that can be
adhesively attached to a housing of the medical device, allowing
implantation of the medical device into a body through an incision
of reduced size. The flexible member can be attached to the housing
either before or after implantation into the body. The flexible
member comprises suture locations, including a permeable membrane
or a suture hole, for suturing the medical device to tissue of the
body. The suture holes can be filled with a substance penetrable by
a suture needle, to minimize tissue ingrowth before or after
suturing.
Inventors: |
Bourne; George; (Boston,
MA) ; Culhane; James; (Westborough, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Navilyst Medical Inc. |
Marlborough |
MA |
US |
|
|
Assignee: |
AngioDynamics, Inc.
Marlborough
MA
|
Family ID: |
32093227 |
Appl. No.: |
14/856680 |
Filed: |
September 17, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14070134 |
Nov 1, 2013 |
9168365 |
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14856680 |
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10277215 |
Oct 21, 2002 |
8574204 |
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14070134 |
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Current U.S.
Class: |
604/288.02 |
Current CPC
Class: |
A61M 5/1415 20130101;
A61M 39/0208 20130101; A61M 2039/0232 20130101; A61M 39/04
20130101; A61M 2039/0211 20130101; A61M 2039/0223 20130101 |
International
Class: |
A61M 39/02 20060101
A61M039/02; A61M 39/04 20060101 A61M039/04 |
Claims
1. An implantable port for fluid access to a target site within a
body, said implantable port comprising: a housing defining an entry
site for the administration, withdrawal or exchange of fluids with
the target site, the entry site comprising a septum, the housing
having a side wall extending from the entry site to a base; a
needle-penetrable region adjacent a perimeter of said implantable
port, wherein the needle-penetrable region comprises a
needle-penetrable material configured to allow complete penetration
by a suture needle to attach a suture, and the needle-penetrable
material extending from the base along the side wall for a selected
distance.
2. The implantable port of claim 1, wherein the needle-penetrable
material extends below the base.
3. The implantable port of claim 1, wherein the needle-penetrable
material is flush with the base.
4. The implantable port of claim 1, wherein the needle-penetrable
material is devoid of any preformed spaces not containing the
needle-penetrable material between the housing and the base.
5. The implantable port of claim 1, wherein the needle-penetrable
material comprises a flexible polymer.
6. The implantable port of claim 5, wherein the flexible polymer
comprises silicone.
7. The implantable port of claim 1, wherein the needle penetrable
region does not extend continuously along a cross-section of a
bottom surface of the implantable port, the cross-section defined
by a perimeter of the bottom surface.
8. The implantable port of claim 1, wherein the side wall is
comprised of a metal material.
9. The implantable port of claim 1, wherein the needle-penetrable
material does not contact the septum.
10. An implantable port for fluid access to a target site within a
body, said implantable port comprising: a housing defining an entry
site for the administration, withdrawal or exchange of fluids with
the target site, the entry site comprising a septum, the housing
having a side wall extending from the entry site to a base; a
needle-penetrable region adjacent a perimeter of said implantable
port, wherein the needle-penetrable region comprises a
needle-penetrable material configured to allow complete penetration
by a suture needle to attach a suture, and the needle-penetrable
material adjacent to the base and adjacent to the side wall.
11. The implantable port of claim 10, wherein the needle-penetrable
material does not contact the septum.
12. The implantable port of claim 10, wherein the needle-penetrable
material does not contact the side wall.
13. The implantable port of claim 10, wherein the needle-penetrable
material extends below the base.
14. The implantable port of claim 10, wherein the needle-penetrable
material is flush with the base.
Description
FIELD OF THE INVENTION
[0001] This invention relates generally to implanted medical
devices used to access subcutaneous regions within a body, such as
vasculature.
BACKGROUND OF THE INVENTION
[0002] Long term access to a patient's body is required for many
medical treatments including antibiotic therapy, hemodialysis
access, chemotherapy regimens, and other treatments that require
repeated administration, withdrawal, or exchange of fluids. In some
cases, internal access to the patient is required for years.
[0003] Subcutaneously implanted access ports are one type of
medical device that can be used for this purpose. These medical
devices often either include or are attached to a catheter used for
the administration, withdrawal, and/or exchange of fluids from the
patient. A pocket is made in the subcutaneous tissue, and the medic
device is placed into the pocket.
[0004] Access ports generally have a molded or rigid housing, with
a fixed number of suture holes. These suture holes protrude from
the housing of the medical device, causing it to have a larger
overall size than it otherwise would have. During implantation, a
physician is thus required to create an incision in the body of
sufficient size to allow insertion of the device. Further, rigid
appendages on the housing of the medical device can make
manipulation of the device within the body of a patient difficult
for a physician.
[0005] Suturing of such a device can be performed by the physician
to secure or stabilize the device. A number of factors determine
whether or not the medical device is sutured in place, including
the pocket configuration, the type of training received by the
physician, and the physician's preference. Once the device is
properly positioned and secured, the pocket is closed.
[0006] There is a wide range of preferences among physicians
regarding the number and location of suture holes. Some physicians
prefer one, two, three, four, or more suture holes. Some physicians
prefer not to have any suture holes, and yet others prefer to have
any suture holes that are present filled with a material such as
silicone to minimize fibrin ingrowth into the suture holes, thereby
facilitating subsequent removal of the device.
[0007] After suturing has been completed, the rigid housing of the
medical device and the associated suture holes do not readily
accommodate movement of the patient. Movement of the patient causes
the tissue to which the medical device has been sutured to move.
The rigidity of the device thus results in increased tension on the
sutures, resulting in discomfort and irritation to the patient.
SUMMARY OF THE INVENTION
[0008] In one aspect, the invention features an implantable medical
device for percutaneous access to a body comprising a flexible
member and a housing defining an entry site for the administration,
withdrawal, or exchange of fluids. The flexible member is attached
to a surface of the housing and stabilizes placement of the medical
device within the body. An adhesive is disposed on a first surface
of the flexible member and attaches the flexible member to the
housing surface. The flexible member can comprise suture locations,
and the suture locations can define one or more suture holes. The
suture holes can be filled with a material to minimize tissue
ingrowth, such as fibrin. The material can be silicone or a
biocompatible polymer, and is preferably penetrable by a suture
needle.
[0009] The flexible member can have a perimeter region penetrable
by a suture needle, which can be formed of materials including
polyurethane, thermoplastics, elastomers, and fiber reinforced
elastomers. The flexible member can also include tabs, which can be
located about a perimeter of the flexible member. The tabs can
define one or more suture holes.
[0010] The flexible member can be coated with a tissue growth
substance and can be shaped and/or textured to conform to tissue
within the body. A second surface of the flexible member can
include an adhesive for attaching the device to tissue within the
body. The flexible member can be preformed to mate with the
housing. It can also be shaped to surround a perimeter of the
housing.
[0011] Another aspect of the invention features a flexible member
for stabilizing the placement of a medical device within a body.
The flexible member includes a flexible substrate that mates with
the medical device, one or more suture locations formed on the
flexible substrate, and an adhesive. The flexible member can be
formed from a material penetrable by a suture needle. Materials
such as polyurethanes, thermoplastics, elastomers, and
fiber-reinforced elastomers can be used to form the flexible
member.
[0012] The flexible member can comprise one or more suture
locations, and these can each define one or more suture holes. The
suture holes can be filled with a tissue growth substance that
inhibits tissue growth. The suture holes can be filled with
substances such as silicone and biocompatible polymers. In one
embodiment, the substance is penetrable by a suture needle.
[0013] The flexible member can also include tabs, and the tabs can
be disposed about the perimeter of the flexible member. The tabs
can be flexible and can be penetrable by a suture needle. The
flexible member can be coated with a substance to inhibit tissue
growth. It can also be preformed to mate with the perimeter of a
surface of the medical device and can have a second surface shaped
to conform to subcutaneous tissue within the body.
[0014] At least a portion of the perimeter of the flexible member
can follow a perimeter of the surface of the medical device to
which the flexible member is attached. The flexible member can
include an adhesive to secure the flexible member to the medical
device. The adhesive, can include methoxy-perfluoropropane,
thixotropic sealants, and water-based adhesives.
[0015] Another aspect of the invention features a method of
manufacturing an implantable medical device that comprises
providing a housing defining an entry site for the administration,
withdrawal, or exchange of fluids, and attaching a flexible member
thereto, for stabilizing placement of the housing within the body.
The flexible member can be formed by cutting a sheet of polymer.
The method can include applying an adhesive to the flexible member
by at least one of spray coating, slot coating, spiral spraying,
melt-blowing, pattern coating, layering, dipping and drying, and
ion deposition.
[0016] Another aspect of the invention features a method of
fabricating a flexible member which includes forming a shape for
mating with an implantable medical device, forming suture locations
about the shape of the flexible member, and applying an adhesive to
the shape. The shape can be formed by cutting from a sheet of
polymer, and suture boles can be formed in the flexible member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] These and other features of the invention are more fully
described below in the detailed description and accompanying
drawings of which the figures illustrate an apparatus and method
for securing an implantable medical device within a body.
[0018] FIG. 1 illustrates a prior art device used to provide access
to provide access to subcutaneous regions within a body, such as
vasculature.
[0019] FIG. 2 illustrates another prior art device with only one
entry site.
[0020] FIG. 3 illustrates a side elevation view of an embodiment of
the invention.
[0021] FIG. 4 illustrates a side and top view of another embodiment
of the invention.
[0022] FIGS. 5-8 are a top view of other embodiments of the
invention.
[0023] FIGS. 9 and 10 are perspective views that show different
ways the flexible member can be attached to a surface of a medical
device.
[0024] FIGS. 11-14 are top views illustrating additional
embodiments of the invention.
[0025] FIG. 15 is a side view of a flexible member shaped to
conform to tissue within the body.
[0026] FIG. 16 is a side view of a flexible member that is
preformed to mate with a medical device.
[0027] FIGS. 17-18 illustrate embodiments of the invention with
different thickness characteristics.
[0028] FIGS. 19 and 20 each illustrate an embodiment of the
invention with different surface textures.
[0029] FIG. 21 is a flow chart illustrating steps that can be used
to manufacture a flexible member of the invention.
[0030] FIG. 22 is a flow chart illustrating steps that can be used
by a physician to prepare the flexible member for use.
[0031] FIG. 23 is a flow chart illustrating steps that can be used
to implant a medical device of the invention.
DETAILED DESCRIPTION
[0032] FIG. 1 shows a prior art access port used by a physician to
provide access to subcutaneous regions within the body, such as
vascallature. The medical device 10 includes a housing 11 and an
entry site 12 for the administration, withdrawal, or exchange of
fluids. The entry site can be a septum. The needle of a syringe,
for example, can be used to administer or withdraw fluids through
the septum. The medical device can be surgically implanted beneath
the skin of a patient.
[0033] The medical device can also include a predetermined number
of suture holes 14 disposed about the base of the housing in fixed
locations. The suture holes can be molded into the housing 11 as
shown. A physician can tie a suture through the suture hole, thus
securing the medical device 10, for example, to adjacent tissue.
The medical device shown has two entry sites 12.
[0034] FIG. 2 illustrates another prior art access port with a
single entry site 12. A catheter 22 is attached to the medical
device 10. Suture holes 14 are disposed about the base of the
housing 11 at fixed locations.
[0035] FIG. 3 is an illustration of an embodiment of an access port
incorporating principles of the invention. The medical device 10
comprises housing 11 and an entry site 12. The shape of the housing
11 defines the entry site 12, as shown. The entry site is used to
administer, withdraw, or exchange fluids with a body, and can
comprise a septum. A physician can penetrate the septum with the
needle of a syringe.
[0036] A flexible member 30 is attached to a surface 32 of the
housing. A perimeter region 35 of the member 30 is non-rigid and
flexible. When flexed, the size of the incision required for
insertion of the medical device in a body can be reduced. Suture
locations 38 are disposed along the perimeter region 35 of the
flexible member 30.
[0037] FIG. 4 illustrates a flexible member 30 having a first
surface 41 and a second surface 44. The first surface 41 comprises
an adhesive, which allows the flexible member to be attached to the
surface of the housing 32. In one embodiment, the flexible member
is preformed tape, having an adhesive surface that easily adheres
to the surface of the housing 32. The tape can take various shapes,
forms, thicknesses, and orientations. The flexible member 30 can be
attached to the housing surface 32 before surgery. Adhesively
attaching the flexible member 30 to housing surface 32 of medical
device 10 allows a physician to implant the medical device within a
body us rig an incision of reduced size. Alternatively, the
flexible member can be attached to the housing surf ice after
implantation into a body. This is accomplished by attaching the
flexible member 30 to the housing 32 after each has been inserted
into the body through the incision. In this embodiment, the
incision size can be reduced still further.
[0038] The flexibility of the member 30 also enhances the
manipulation and placement attributes of the device, providing a
physician with increased capabilities and reducing aggravation and
irritation to a patient. Patient recovery and comfort are thus
enhanced. The flexible member also results in improved comfort and
reduced irritation to the patient after the medical device has been
implanted. Movement of a patient causes the tissue to which the
medical device has been sutured to move. The resiliency of the
flexible member thus reduces the stress to the body tissues of the
patient during movement of the patient. This results in reduced
irritation to the body and increased patient comfort. If sutures
are present (discussed below), the benefit of this feature is
increased.
[0039] The perimeter region 35 of the flexible member 30 can extend
beyond the perimeter 47 of the housing surface. As shown, the
perimeter region 35 of the flexible member 30 can extend beyond the
perimeter of the housing surface 47 on all sides. In other
embodiments, the perimeter region 35 can extend beyond the
perimeter 47 of the housing surface on fewer than all sides.
[0040] FIGS. 5-8 show a top view of different embodiments of the
invention. FIGS. 5 and 6 illustrate a flexible member comprising a
perimeter region 35. This perimeter region 35 can extend beyond the
perimeter of the housing surface 47 when the flexible member is
attached to surface 32 of housing 11. The perimeter region 35 ran
extend beyond the housing perimeter 47 in all directions, as shown.
In other embodiments, it extends beyond the housing perimeter 47 in
fewer directions. In any of these embodiments, a plurality of
suture locations 38 can he disposed about the perimeter region 35
of the flexible member 30.
[0041] FIGS. 7 and 8 illustrate flexible members 30 comprising
preformed tabs 72 that extend beyond the perimeter of the housing
surface 47. Each of these tabs 72 can include one or more suture
locations 38.
[0042] Each of the embodiments found in FIGS. 5-8 can be formed as
a preformed flexible member. The shapes illustrated in these
figures are intended to conform generally to the perimeter of the
housing surface 47 to which they can be attached. In other
embodiments, however, the flexible member may not cot form to the
perimeter of the housing.
[0043] FIG. 9 illustrates the manner in which an embodiment of the
flexible member 91 can be joined with the housing surface 32A of
medical device 10. Tabs 72 comprising suture locations 38 extend
beyond the perimeter of the housing surface 47A providing locations
to which a suture can be conveniently attached.
[0044] FIG. 10 illustrates a perspective view of another embodiment
of a flexible member 101 that can be joined with the housing
surface 32A of medical device 10. In this embodiment, the perimeter
region 35 comprises suture locations 38 and extends beyond the
perimeter of the housing surface 47A. As shown in FIGS. 9 and 10,
both embodiments of the flexible member (91, 101) can be
effectively attached to housing surface 32A and efficiently mate
with the perimeter 47A of the housing surface. When attached to the
housing surface 32A, both embodiments (91 and 101) of the flexible
member adhere to the entire housing surface 32A, in other
embodiments, this may not be required. Rather, the flexible member
can be shaped to adhere to only a portion of the housing surface.
This is useful if it is necessary to stabilize only a portion of
the medical device.
[0045] FIG. 11 illustrates an asymmetrical embodiment of the
invention. In particular, the perimeter region 35 extends further
in the direction labeled as "A" than in the other directions. Thus,
the dimension of the perimeter region 35 of the flexible member 30
is larger in direction A than in the other direction shown. This
embodiment includes a plurality of suture locations disposed in the
perimeter region 35. The presence, location, and number of suture
locations are determined by the needs and preferences of the
physician using the device.
[0046] FIG. 12 illustrates an embodiment of the flexible member 30
comprising suture locations 38 disposed both in a perimeter region
35 and on tabs 72. It is not necessary for all or any of the suture
locations 38 to be sutured by a physician. This embodiment also
illustrates that more than one suture location 38 can be present on
a tab 72.
[0047] FIG. 13 illustrates an embodiment of the flexible member 30
comprising a hole, 131 in the center of the flexible member.
Further, the suture locations 38 are asymmetrically disposed about
the perimeter region 35 of the flexible member 30. This and other
embodiments of a flexible member can be used to fulfill customized
surgical requirements.
[0048] FIG. 14 illustrates a bottom view of an embodiment in which
the flexible member 30 extends beyond the perimeter of the housing
surface 47 at two areas, labeled as X' and X'' on the figure.
Suture locations 38 are present at perimeter regions 35' and 35''.
As shown, portions of the housing surface 32 are not in contact
with the flexible member 30. A physician can also use this
embodiment to meet varying surgical requirements and preferences.
For example, in this embodiment exposed housing surfaces 142 and
143 are not in contact with flexible member 30. Thus, a physician
can grasp these surfaces directly and use them to manipulate the
medical device during implantation of the medical device into a
body. The desirability and utilization of this and other specific
embodiments of the invention varies widely among physicians.
[0049] FIGS. 15-18 illustrate various thickness characteristics of
the flexible member 30 of the invention. Each of these embodiments
can include tabs 72 and perimeter regions 35. In FIG. 15, the
thickness of the flexible member 30 varies along us length. The
medical device. 10 is illustrated as being surgically positioned
between a cutaneous layer 151 and a tissue layer 154. The flexible
member 30 includes a region of increased thickness 156 and a region
of lower thickness 157. The varying thickness of the flexible
member allows it to fit snugly between the surface of the housing
32 and the tissue layer 154. As shown, the contour of the second
surface 44 of the flexible member is shaped to conform to the shape
of the tissue layer 154. Although the first surface 41 of the
flexible member can also be contoured, this is not necessary in all
embodiments.
[0050] FIG. 16 illustrates a flexible member 30 having a
non-uniform variation in its thickness. Thickness variations such
as these are used to match the shape of muscle, other tissue formed
within the body, and the like. This feature can used to improve the
placement stability of the medical device within a body.
[0051] FIG. 17 illustrates a bottom view of yet another embodiment
in which the second surface of the flexible member 44 comprises
ridges 171 for stabilizing placement of the medical device 10.
Ridges such as these are useful for preventing longitudinal motion
of the flexible member when in contact with the body tissue.
[0052] Referring to FIG. 18, the shape of the flexible member can
be preformed to mate with a perimeter of the medical device. The
flexible member 30 comprises extensions 182 that are formed to mate
with the surface of the housing 32, and are positioned at points
about the perimeter 47 of the housing surface. In one embodiment,
these extensions 182 form a continuous ridge on the first surface
41 of the flexible member, encircling the perimeter 47 of housing
surface 32 and facilitating accurate alignment with the housing 11.
The first surface 41 can be coated with an adhesive to facilitate
attachment to the surface of the housing 32.
[0053] FIGS. 19 and 20 illustrate embodiments comprising a second
surface 44 of the flexible member with different textures. These
textures can include, for example, bumps or hair-like tentacles.
These textures canoe unidirectional (as shown in FIG. 20) or can be
oriented in multiple directions. Textures can be formed as an
integral part of the flexible member, or they can be attached to a
surface of the flexible member after it has been formed. Although
FIGS. 19 and 20 show the entire second surface 44 of the flexible
member covered with a texture, in some embodiments only a portion
of the second surface 44 is covered. Moreover, combinations of the
different types of textures can be used on the same flexible
member. The first surface 41 of the flexible member can also have a
texture, although a smooth surface is generally preferred to
promote more effective adhesion with the housing surface 32.
[0054] The suture locations 38 can be an important element of some
embodiments of the invention. In one embodiment, the suture
locations 38 comprise permeable portions of the perimeter region 35
of the flexible member 30, such as a permeable membrane. For
example, the suture locations in each of the embodiments described
above comprising a perimeter region 35 can have one or more suture
locations 38 including a permeable membrane. A permeable membrane
is any biocompatible material that a physician can penetrate with a
suture needle, either before or during implantation of the medical
device within the body of a patient. A perimeter region 35 can
comprise zero, one, or a plurality, of suture locations.
Furthermore, in some embodiments the entire perimeter region 35 can
be penetrable by a suture needle, and thus can function as a large
suture location 38. In still other embodiments, the entire flexible
member 30 can be penetrable by a suture needle.
[0055] For embodiments comprising a permeable membrane, the suture
location 38 is generally made of as material that closes back about
the suture or suture needle after the material has been penetrated.
Suture locations such as these can be penetrated one time or
multiple times by a suture needle. Generally, a physician
penetrates a given point within a suture location only once with a
suture needle, although the same point on a suture location can be
penetrated multiple times. However, a suture location can readily
be sutured multiple times by a physician if multiple sutures are to
be attached to that suture location, and these sutures can be
positioned at the same or different points. The suture location
thus comprises a permeable membrane that can be penetrated at
multiple different locations. Multiple sutures can thus be located
adjacent to each other, can be scattered about the suture location
38, or can be scattered about the perimeter region 35, all at the
discretion of the physician. This is a useful feature in that a
physician does not have to determine before surgery if, or how
many, sutures are needed, or precisely at what locations about the
medical device 10 they will be placed.
[0056] The decision to attach any sutures to the medical device at
all is at the discretion of the physician. Stabilization of the
placement of the medical device 10 within a body using the flexible
member 30, without suturing, and either with or without the
presence of suture locations, represents a preferred embodiment for
some physicians.
[0057] In other embodiments, suture holes 14 may be punched into
suture locations 38. Suture locations 38 in each of the embodiments
described above can have one or more suture holes 14. The use of
suture holes 14 eliminates the need for a physician to force a
suture needle through the material of the suture location 38. More
than one hole may be located in a suture, location, and suture
holes can be conveniently punched into the flexible member 30
before surgery using simple tools. Alternatively, suture holes 14
can be preformed at suture locations 38 about the perimeter region
35 of flexible member 30 at the time of manufacture.
[0058] In some embodiments prepunched patterns are formed, for
example, in the perimeter region 35 or on the tabs 72 of the
flexible member 30 to facilitate the creation of suture holes 14.
Holes prepunched in this manner each have an easily removable plug,
the removal of which creates suture holes 14 ready for use by a
physician.
[0059] Although reference to sutures, suturing, and suture needles
has been made above, the invention is equally applicable to
staples, hooks, and other devices and means known to those of skill
in the art for placing, securing, or attaching devices within a
body. Use of the terms suture and suturing is intended to include
these other devices and methods.
[0060] Furthermore, the above discussion has centered on suture
locations 38 disposed within the perimeter region 35 specifically,
and generally within the flexible member 30. However, the invention
also includes suture locations 38 disposed within tabs 72, as
discussed above. These suture locations can include suture holes
14, or not. As with the flexible member 30 and the flexible region
35, these tabs are preferably foldable and flexible.
[0061] In embodiments, the suture holes 14 can be filled with a
filling material. This filling material can be added to the suture
hole 14 before surgery, and preferably during manufacture of the
flexible member 30. The filling material should be formed of a soft
material such as silicone that can be penetrated by a suture
needle, and that will close about a suture after suturing. Other
materials can be used to fill the suture holes 14, such as
CORETHANE.RTM. (registered mark of Corvita Corporation, Miami,
Fla.), polyurethane, and bionate polycarbonate urethanes. Materials
with a Durometer reading of 50-55 are preferred for this purpose.
Such materials are relatively soft, and can be conveniently
punctured with a needle. An appropriate material thickness should
be used, as is apparent to one of ordinary skill in the art. The
suture holes 14 can be filled or pre-filled with the filling
material. The presence of the filling material in the suture hole
14 minimizes tissue ingrowth into the suture hole, making
subsequent removal of the medical device less difficult.
[0062] Additionally the flexible member 30, and the medical device,
can be coated with a material, for example, to inhibit tissue
ingrowth. Suitable coatings include but are not limited to
antimicrobial coatings for the prevention of microbial biofilming,
hydrogel coatings, zinc oxide coatings for preventing surface
irritation, various block copolymers, tackifying resins, and
polybutene. The medical device and the flexible member can also be
impregnated with an antimicrobial substance, preferably at least in
a portion of the device that will be located near the cutaneous
layer 151.
[0063] FIG. 21 is a flow chart illustrating steps that can be used
to manufacture a flexible member. First the desired shape,
thickness, contours, and textures of the flexible member are
determined (step 211). The locations of all the desired suture
locations 38 are next determined (step 212). Which suture locations
38 will comprise tabs 72 and which will comprise perimeter regions
35 is next determined. Since tabs can easily be removed later,
additional tabs can be included that perhaps might not be used
during implantation of the device. A pattern can be created for the
flexible member (step 214) and a suitable polymer sheet selected
(step 215). Preferably, the thickness regions 156, 157, extensions
182, surface textures, and contours of the flexible member are
achieved by selecting a polymer sheet possessing the desired
characteristics.
[0064] A shape corresponding to the pattern can then be cut from a
polymer sheet (step 216), such as silicone. Any pre-planned suture
holes 14 can next be added to the tabs 72 and the perimeter regions
35 (step 217). These, can be added, for example, by puncturing.
Optionally, any suture holes 14 that have been tanned in step 217
can be filled with a substance to inhibit tissue growth into the
suture hole (step 218). Finally, at the discretion of the
physician, additional suture holes can be added to suture locations
38 and any unwanted tabs 72 can be severed from the flexible
member, at the time of surgery (step 219).
[0065] To complete the manufacture of a medical device, a housing,
such as that of an implantable port, is provided. The flexible
member is then attached to a surface of the medical device. When
implanted within the body, the medical device exhibits improved
placement stability.
[0066] Other embodiments of the manufacturing process are also
possible. For example, an adhesive coating can be applied to the
flexible member after it has been cut from the polymer sheet, or
the polymer sheet can comprise an adhesive material before the
cutting is performed. Preferably, the adhesive is applied to the
sheet of polymer material by at least one of slot coating, spiral
spraying, melt blowing, pattern coating, layering, dipping/drying,
and ion deposition.
[0067] Suitable biocompatible adhesives are known to those of
ordinary skill in the art, and include water-based adhesives,
methoxy-perfluoropropane, and thixotropic sealants. Such adhesives
can be coated continuously or discontinuously, and are compatible
with muscle, tissue, skin surfaces, and the like. The first surface
41 of the flexible member comprises such an adhesive, for
contacting the housing surface 32. Optionally, the same or a
different adhesive can be applied to the second surface 44 of the
flexible member, for contacting tissue layer 154. Tissue-specific
adhesives can also be used. The application of adhesive to tie
second surface 44 of the flexible member contributes to the
placement stabilization of the medical device 10. Adhesives of low
or moderate tacking strength can also be used on either surface, to
facilitate repositioning or removal of the flexible member.
Preferably, the adhesive selected for this purpose will not leave a
residue or exhibit any adhesive transfer to the tissue surface 154
upon removal or relocation of the medical device 10. Materials left
behind after removal of the medical device can adversely affect
healing of the body.
[0068] The flexible member 30 can be manufactured from many
different materials. Preferably, the flexible member is formed from
at least one of thermoplastics, elastomers, polyurethanes, and
fiber reinforced elastomers. Suitable fibers for this purpose
include polyester or Kevlar.RTM. fiber. Kevlar.RTM. is a registered
trademark of E.I. duPont de Nemours and Company. The flexible
member can also be manufactured from materials such as a
latex/plastic polymer blend, silicone, vinyl, foam, rubbers,
varying percentages of rubbery block co-polymers and midblocks
comprising ethylene/propylene and ethylene/butylene, and mixtures
thereof, S-EP block co-polymers (styrene-ethylene/propylene),
dycyclopentadiene, fully hydrogenated aliphatic C5 and C9 resins,
and alpha-methylstyrene based resins.
[0069] Various packaging and usage options are within the scope of
the invention. For example, a package can be sold that includes a
set of pre-cut flexible members or "frames." The physician can then
select the desired style from the set, attach it to the medical
device, and perform the implantation. The package can include
Flexible members with, for example, a one, two or three-hole
option. The physician merely selects the flexible member that meets
his needs and preferences. Optionally, if desired, the medical
device can be trimmed and/or suture holes can be added, before
attaching a flexible member.
[0070] FIG. 22 is a flow chart illustrating steps that can be used
by a physician to select and prepare the flexible member for use. A
physician opens a package containing a number of flexible members
(step 221). One of the flexible members from the package is
selected. The flexible member selected should have tabs 72 and
perimeter regions 35 in at least each of the locations desired
(step 222). Extra, unwanted tabs can be removed by cutting (step
223). Any additional suture holes 14 can be added (step 224), for
example, by puncturing. Optionally, a filling material such as
silicone can be added to any suture holes that have not been
prefilled, to prevent or minimize tissue ingrowth. These unfilled
suture holes can be filled by the physician or his staff before
surgery, or after implantation into the body of a patient
(described below). The unfilled suture holes could have been
formed, for example, in either step 224 or step 217.
[0071] FIG. 23 is a flow chart illustrating steps that can be used
to implant and secure a medical device 10 comprising a flexible
member 30 into a body. Various methods can be used for this
purpose. The physician first determines the location and number of
suture locations desired and prepares the flexible member as
described in FIG. 22 (step 231). If the flexible member has tabs
72, any undesired tabs are removed. If insufficient suture holes 14
are present, more can be added by puncturing the appropriate suture
location(s) of the flexible member.
[0072] More than one suture hole can be added to each suture
location, depending upon the physician's preference.
[0073] A linear incision is made in the patient (step 232). The
incision is of reduced size, due to the planned usage of the
flexible member. The flexible member can be adhesively attached to
the housing surface 32 at this time (step 233), or it can be
attached later. Attaching it later allows the smallest incision
size to be used.
[0074] The housing 11 and the flexible member 30 are inserted
through the incision, into the body of the patient, near an area in
which the catheter 22 is to be placed. The physical positions the
catheter, and then positions the flexible member adjacent the
tissue layer 154 (step 236). The flexible member is then sutured
into place (step 237). This can be done by sewing subcutaneous
sutures through the suture locations 38, thereby securing the
flexible member 30 to adjacent tissue. The flexible member is now
attached to the housing surface 32, if it has not already been
attached (step 238). The incision is then closed and bandaged (step
239).
[0075] The sutures can thus be used to anchor the tissue layer 154
and/or the cutaneous layer 151 to the medical device 10. In other
embodiments tissue can be anchored the medical device using
subcutaneous hooks and other devices and methods known to the
skilled artisan.
[0076] In some embodiments the flexible member 30 or the housing 11
can be coated with materials that promote tissue growth to provide
better sealing of the incision, such as collagen or other tissue
growth catalysts and substances. Materials that promote ingrowth of
cells, such as a permeable fabric, a textured polymer, or
appropriate mesh materials can also be bonded to or embedded into
the surface of medical device 10. The added ingrowth materials
cause the skin surrounding the medical device 10 to bond securely
with the medical device 10. Alternatively, growth inhibition
materials can be placed on or around the medical device. For
example, suture holes 14 that will not be used can be filled with
silicone to prevent tissue ingrowth. Thus, fibrin will not grow
into these suture locations, and the medical device can later be
more easily removed.
[0077] The flexible member of the invention is suitable for use
with various medical devices including implantable venous ports,
PEG ports, and other epidermal and indwelling medical devices that,
for example, provide access to the body or to vasculature. These
include devices used for gastrointestinal feeding and metering,
intervascular pumps, insulin pumps, drainage products (such as for
draining an abscess), pacing products (such as pacemakers), and
various catheters.
[0078] While the invention has been particularly shown and
described with reference to specific preferred embodiments, it
should be understood by those skilled in the art that various
changes in form and detail may be made therein without departing
from the spirit and scope of the invention as defined by the
appended claims.
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